Q: AC system malfunction

asked by on July 27, 2016

The air conditioning in my car is malfunctioning. When the weather is hot, it starts blowing hot air. I tried to solve the problem by installing the new circuit board. It controls all the modes of the AC but it still doesn't function normally. Also, I had the evaporator and compressor replaced. How can I fix the AC system?

AC Condenser Replacement $455.98 - $1342.51 Get a Quote
AC Pressure Switch Replacement $176.05 - $501.42 Get a Quote
AC is not working Inspection $111.46 - $131.46 Get a Quote

Hello. It is possible that there may be a clog in the A/C condenser or the A/C pressure switch. It is also possible that your Lexus SC430 may have a refrigerant leak. I would recommend that you have a certified technician, like one from YourMechanic, come out and complete an inspection in order to pinpoint why your A/C is not working.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing


Experienced Mechanic?

Earn up to $70/hr

What others are asking

Transmission grinding when in gear.
Differential failure is a likely cause of this symptom. A faulty CV axle or transmission failure are also likely causes. I would recommend having your transmission and differential inspected by a professional to ensure all parts are working correctly.
Maintenance Suggestions
When you bought your car, along with the owners manual, there is a factory recommended service schedule booklet. Following the recommendations on that booklet is crucial while the car is under factory warranty. If the services the manufacturer recommends at...
Hood release not working
It sounds like the cable for the hood release has broken. These cables usually break at the connector under the dash. If this is the case, you can still open the hood; just find where the cable connects, and pull...
My check engine light is on reading code po171 lean
The code P0171 (https://www.yourmechanic.com/article/p0171-obd-ii-trouble-code-system-too-lean-bank-1-by-andrew-quinn) is for the engine control module is getting an O2 sensor lean bank 1 problem in the engine and has tried to compensate by making the injection system go rich on that bank. There is a...
Keep blowing a tail light fuse.
Assuming that no wiring was damaged during the install of the aftermarket lights, (i.e., cut insulation causing a short to ground), if the fuse started blowing right after the install that means the LED assembly is drawing more current than...
AWD light stays on 2009 Nissan Murano
Hello - check the fuse(s) for your AWD (https://www.yourmechanic.com/article/how-all-wheel-drive-works) first. The engagement mechanism is an electrical solenoid in the transfer case, and it's possible that the solenoid has over-loaded, or failed. For additional assistance, I recommend a AWD problem (https://www.yourmechanic.com/services/electrical-components-are-not-working-inspection)...
Wheel is free but the key won't turn
You should try a different key if you have a spare one to try. If the spare key turns the ignition now then the original key is worn and needs replaced.If you do not have an extra key then look...
Power Steering return hose leak
Hi There, You are likely correct in that if the leak is not coming from the high pressure line, it may be leaking from the return lines. I would suggest having a professional from YourMechanic come to your location to...
Engine revs way up when started, then behaves normally. If the car has recently been started, it doesn’t have this issue.
It is normal for the engine rpm to go up to about 1200 to 1400 rpm when first started and then comes down gradually. This is for emissions during cold start and considered normal. If you feel it is not...

Related articles

A Buyer’s Guide to the 2012 Lexus LS 600h L
The The “h” stands for hybrid, and while you might hope to get greatly improved gas mileage for your effort to go green, that shouldn’t be your motivation for buying this model. The 600h L offers a mere 1 mpg...
Symptoms of a Bad or Failing Air Suspension Air Compressor
If your car is riding lower than usual, making abnormal sounds, and its compressor won't start, you may need to replace the air suspension compressor.
How Long Does an AC Belt Last?
Your Your AC belt connects the crankshaft of your car’s engine to the air conditioning unit, delivering cool air to you in hot weather, and also working to defrost your windows when the temperature drops. Depending on the type of...